Influence of Phosphorus on Initial Growth and Production of Fresh Biomass of Legumes

Abstract

Aims: To evaluate whether the initial growth and production of green biomass of the legume species Crotalaria juncea L. and Canavalia ensiformis (L.) DC. are influenced by phosphate fertilizer.
 Study Design: A completely randomized design was used in a scheme 05 treatments x 02 cultures, with 3 replications, totaling 30 vessels in the experiment.
 Place and Duration of Study: Forest nursery the Federal University of Campina Grande, campus of Patos-PB, between April 2018 and May 2018.
 Methodology: The treatments consisted of two legumes (C. juncea and C. ensiformis) and five doses of phosphorus (00-50-100-150-200 mg kg-1 of P2O5) through single super phosphate. Fortnightly measurements of height and diameter were performed for 60 days. Fresh biomass of the shot and root was obtained at the end of the evaluations.
 Results: There is a higher growth in height for individuals of C. ensiformis when cultivated in doses of 150 mg kg-1, with an average of 30.68 cm. For C. juncea, the treatments were similar. For the stem diameter, there was significant interaction (p <0.05) only for C. juncea, in which, unlike the results obtained for height, this variable grew linearly with increased phosphorus doses. Regardeless of the P doses fresh biomass production of C. ensiformis was higher than to C. juncea. Already in function on the levels of P there is an influence of nutrient only for C. ensiformis, with higher total biomass production and when cultivated with 100 mg kg-1 of P2O5.
 Conclusion: Regardless of the cultivated species phosphorus influences the initial growth and production of fresh biomass. In general, it is recommended to cultivate the legumes studied with doses of 100 mg kg-1 of P2O5 through single super phosphate for a higher production of total fresh biomass.